In response to a previous post: The reason they don't include the selling price of the various permutations of spiderling silk combines is that they are a NO-FAIL combine. Why the hell would anyone pay extra for something that only takes a few clicks. I had a guy try to sell me a stack of spider silks for 2pp and said he would turn them all into silk swatches for 4pp. What a deal.
It's still a pain to do the combine. If you buy the swatches at the premium, you are basically paying him for his time. Whether that is fair or not is up to the individual.